<html>
	<head>
		<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />	
		<script type="text/javascript">
			var a = [1,2,3];
			
			var b = 4;
			alert(a.indexOf(b));
		
		</script>
	</head>
	
	<body>
	
	</body>
</html>